Cernosvitoviella atrata (Bretscher, 1903)

(Figures 1 C, 7–8)

Marionina atrata Bretscher, 1903: 5, 17.

Enchytraeoides atratus (Bretscher) . Černosvitov 1928: 14 –16, text fig. 3, pl. I figs. 8, 9. Cernosvitoviella atrata (Bretscher) . Nielsen & Christensen 1959: 38 –39, figs 15–18. Kasprzak 1986: 109 –111, figs. 225, 252– 260. Chalupský 1992: 140 –141, fig. 7. Rota 1995: 193. Rota & Healy 1999: 31. Timm 2009: 148 –149. Schmelz & Collado 2010: 57, 62. Schmelz et al. 2015: 516 –517.

Material investigated: (in total 15 specimens), 1 specimen from site 1 (31.10. 2014), 7 specimens from site 2 (13.10.2014), 5 specimens from site 6 and 2 specimens from site 7 (31.03.2014).

Body 3–5 mm long, 150–200 µm wide at VIII and 170–250 µm at XII, segments 22–25. Chaetae (Fig. 7 G) sigmoid with nodulus, up to 6–7 per bundle, 3 2–40 µm long. Clitellum absent dorsally and ventrally. In the prostomium about 8 large rounded papillae (Fig. 7 B). Brain (Fig. 7 A) incised posteriorly, about 10 µm long and 1.5 times longer than wide. Two pairs primary and two pairs secondary pharyngeal glands (Fig. 8 A,B). Coelomocytes 14–20 µm long, variable, mostly oval, without (Fig. 7 C) or with refractile granules, brown in transmittent light and often have long fine hyaline plasma threads (Fig. 7 D). Dorsal vessel origin in XII–XIII. Blood light pink. Seminal vesicle absent. Sperm funnels funnel-shaped (Fig. 7 E,H,I) 55–80 µm long, vas deferens 150–300 µm long and 15– 20 µm wide proximally and gradually tapering to 8–11 µm width distally. Male opening (Fig. 7 E–F) surrounded with glands, diameter 35–55 µm. Spermatozoa 30–50 µm long, heads 15–25 µm. Spermathecae (Figs. 1 C, 8A–D) confined to V, ampullae elongate, about as long or somewhat shorter than the length of the ectal ducts, sperm arranged lengthwise.